Lithospermic acid, the active principle of a variety of herbal preparations prepared from Lithospermum ruderale and Lithospermum officinale has been shown to inhibit the in vivo and in vitro activity of TSH, LH, FSH, oxytocin, and glucagon but not insulin or ACTH. Preliminary pharmacological findings show promise in the treatment of diabetes, hyperthryroidism, and in fertility control. A total synthesis of this important compound is proposed involving as a central intermediate an appropriately protected 5,6-dihydroxy-2-benzopyran-3-one. Possibilities for the preparation of active analogues exist.